Components operating in the front inlet of gas turbine aircraft engines are vulnerable to the erosive effects of environmental conditions such as rain, snow and sleet. Various protection methods and protective coatings are currently being used to protect the components from these wear producing environmental variations. The most commonly used method involves applying an overlay coating to portions of the gas turbine engine in order to protect the underlying substrates. These overlay coatings typically exhibit some environmental erosion resistance and are synthetic rubber based with additives included to tailor the overlay coating to specific consumer specifications.
Application of the overlay coatings is typically accomplished by manually laying up the coating on the unprotected substrate. The manual ply lay-up method requires a cutting of the overlay coating from a premanufactured sheet of solid protective overlay coating, wherein the overlay coating is cut and fitted to near shape the component to be coated. The surface of the substrate is then prepared to receive the overlay coating by such methods as are necessary to ensure that the coating will adhere to the substrate. Once the substrate is prepared to receive the coating material, the coating material is manually placed on the substrate to be coated. The coating material is then pressure bonded onto the substrate usually by autoclave or hydraulic press. After the coating material is pressure bonded onto the substrate, the combination is finally post cured by conventional methods. The manual lay up process typically involves about ten steps to complete.
The traditional coating application method presents significant design challenges in that it is both time consuming and costly. Use of the manual ply lay-up method is time consuming in that it involves applying the protective coating to the substrate in a ten-step process done essentially by hand. The method is costly in that it requires multiple manual manipulations to complete. Consequently, the disadvantages inherent in the traditional overlay coating technique demonstrates a need for a method, which is less costly and time consuming than the manual ply lay-up coating. A suitable coating method requires less manual manipulations and involves less process steps and manpower to complete.